The phrase "avid backer" is correct and usable in written English.
It can be used to describe someone who is very enthusiastic and supportive of a particular cause, project, or individual.
Example: "As an avid backer of renewable energy initiatives, she donates regularly to various environmental organizations."
Alternatives: "enthusiastic supporter" or "passionate advocate.".
And I'm an avid backer of the free enterprise system.
Beyond his opposition to Mr. Obama, Mr. Adelson is deeply involved in Israeli politics and is an avid backer of Republican Jewish organizations.
The president, an avid backer of the Public Affairs, is said to not have been happy with that.Nor helped Mr Nečas' rhetorical blunders.
No one made much of his split with Mrs. Clinton since he was such an avid backer of the junior senator from his home state.
Joseph J. Grano, who runs the brokerage operations of UBS, the Swiss bank, has been an avid backer of President Bush and the Republican convention.
It will be the ultimate political showdown: SeaWorld is owned by the Blackstone Group, a huge venture capital firm run by billionaire Stephen Schwarzman -- an avid backer of Mitt Romney who once compared Obama's economic policy to that of Hitler.
Many of his most avid backers, polls show, are the same low-educated, working-class Americans who have struggled economically.
He can read the polls and while those polls harp on his plunging popularity numbers, he sees that his avid backers, and there are millions of them, are unwavering in their support of him.
Backers have raised about $2.5 million.
North Carolina political consultant Gary Pearce played this down, saying it may simply reflect a lack of candidates -- many Southern Democratic leaders were not avid Obama backers, and one obvious prospect, former North Carolina senator John Edwards, has been tarnished by scandal.
This new balloon involves a cadre of avid Bush backers suddenly saying "He's an idiot".
